Combined component for afterburning anode exhaust gases from a fuel cell system and for vaporizing educts delivered by the fuel cell system

Abstract

A combined component for afterburning anode exhaust gases from a fuel cell system and for vaporizing educts to be fed to the fuel cell system has an exhaust gas catalyzer for afterburning the anode exhaust gases, with a substantially cylindrical casing having an inlet and an outlet connection disposed coaxially to the long axis of the casing, one on a casing cover and the other on a casing bottom. A first gas-permeable inner tube is disposed coaxially to the long axis of the casing and fixedly joined at the gas inlet end to the casing cover, while a second gas-permeable outer tube which is also disposed coaxially with the long axis of the casing and has a radius r A greater than the radius r I of the inner tube but smaller than the radius r G of the casing. The latter is connected gas-tight to the casing cover at the inlet end. A bulk catalyst is disposed in the area between the inner and the outer tube for the catalytic oxidation of the anode exhaust gas. At least one educt to be fed to the fuel cell system is provided in the area between the inner tube and the outer tube, and at least one set of educt flow tubes of the evaporator, through which the educt to be evaporated flows, are carried around the inner tube of the exhaust gas catalyst.

What is claimed is:  
     
       1. A combined component for a fuel cell system, comprising: 
       an exhaust gas catalyzer for afterburning anode exhaust gases from the fuel cell system; and  
       an evaporator for evaporating at least one educt to be fed to the fuel cell system; wherein  
       the exhaust gas catalyzer includes  
       a casing with a casing cover and a casing bottom,  
       a gas inlet and a gas outlet connection disposed on the casing cover and on the casing bottom respectively,  
       a gas-permeable inner tube arranged coaxially with a long axis of the casing affixed to the casing cover, and  
       a gas-permeable outer tube disposed coaxially with the long axis of the casing joined to the casing cover,  
       a catalyst material in an area between the inner and the outer tube for the catalytic oxidation of the anode exhaust gas,  
       the outer tube having a radius (r A ) greater than the radius (r I ) of the inner tube, yet smaller than the radius (r G ) of the casing; and  
       the evaporator is disposed between the inner tube and the outer tube, and includes  
       at least one inlet tube,  
       an outlet tube, and  
       at least one set of educt flow tubes connected between said at least one inlet and said outlet tube and passing around the inner tube.  
     
     
       2. The component according to  claim 1 , wherein said at least one set of educt flow tubes is substantially semicircularly parallel to one another. 
     
     
       3. The component according to  claim 1 , further comprising as part of the evaporator: 
       a second inlet tube and a second set of educt flow tubes.  
     
     
       4. The component according to  claim 3 , wherein both sets of educt flow tubes spiral at least once around the inner tube. 
     
     
       5. The component according to  claim 1 , wherein said at least one set of educt flow tubes has sections of reduced cross section. 
     
     
       6. The component according to  claim 3 , wherein said at least one set of educt flow tubes has sections of reduced cross section. 
     
     
       7. The component according to  claim 5 , wherein said at least one set of educt flow tubes have linings which create sections of reduced cross section. 
     
     
       8. The component according to  claim 6 , wherein said at least one set of educt flow tubes have linings which create sections of reduced cross section. 
     
     
       9. The component according to  claim 1 , wherein an inner surface of said at least one set of educt flow tubes is textured. 
     
     
       10. The component according to  claim 3 , wherein an inner surface of said at least one set of educt flow tubes is textured. 
     
     
       11. The component according to  claim 1 , wherein an outer surface of said at least one set of educt flow tubes is textured. 
     
     
       12. The component according to  claim 3 , wherein an outer surface of said at least one set of educt flow tubes is textured. 
     
     
       13. The component according to  claim 1 , wherein an outer surface of said at least one set of educt flow tubes is catalytically coated. 
     
     
       14. The component according to  claim 3 , wherein an outer surface of said at least one set of educt flow tubes is catalytically coated.